<receiver
  android:name="com.itydl.lockscreen.DeviceAdminSample"
  android:description="@string/sample_device_admin_description"
  android:label="@string/sample_device_admin"
  android:permission="android.permission.BIND_DEVICE_ADMIN" >
  <meta-data
   android:name="android.app.device_admin"
   android:resource="@xml/device_admin_sample" />

  <intent-filter>
   <action android:name="android.app.action.DEVICE_ADMIN_ENABLED" />
  </intent-filter>
 </receiver>

 <string name="activity_sample_device_admin">设备管理员</string>
<string name="sample_device_admin">管理员</string>
<string name="sample_device_admin_description">开启设备管理员，不开启扣2000块</string>

 <device-admin xmlns:android="http://schemas.android.com/apk/res/android">
 <uses-policies>
 <limit-password />
 <watch-login />
 <reset-password />
 <force-lock />
 <wipe-data />
 <expire-password />
 <encrypted-storage />
 <disable-camera />
 </uses-policies>
</device-admin>

dpm = (DevicePolicyManager) getSystemService(DEVICE_POLICY_SERVICE);
 ComponentName who = new ComponentName(this, DeviceAdminSample.class);

<string name="activity_sample_device_admin">设备管理员</string>
<string name="sample_device_admin">管理员</string>
<string name="sample_device_admin_description">开启设备管理员，不开启扣2000块</string>

  DevicePolicyManager dmp = (DevicePolicyManager) getSystemService(DEVICE_POLICY_SERVICE);
  dmp.lockNow();//一键锁屏

<?xml version="1.0" encoding="utf-8"?> 
<manifest xmlns:android="http://schemas.android.com/apk/res/android" 
 package="com.itydl.lockscreen" 
 android:versionCode="1" 
 android:versionName="1.0" > 
 
 <uses-sdk 
  android:minSdkVersion="8" 
  android:targetSdkVersion="17" /> 
 
 <application 
  android:allowBackup="true" 
  android:icon="@drawable/ic_launcher" 
  android:label="@string/app_name" 
  android:theme="@style/AppTheme" > 
   
  <activity 
   android:name="com.itydl.lockscreen.MainActivity" 
   android:label="一键锁屏" > 
   <intent-filter> 
    <action android:name="android.intent.action.MAIN" /> 
 
    <category android:name="android.intent.category.LAUNCHER" /> 
   </intent-filter> 
  </activity> 
 
 
  <receiver 
   android:name="com.itydl.lockscreen.DeviceAdminSample" 
   android:description="@string/sample_device_admin_description" 
   android:label="@string/sample_device_admin" 
   android:permission="android.permission.BIND_DEVICE_ADMIN" > 
   <meta-data 
    android:name="android.app.device_admin" 
    android:resource="@xml/device_admin_sample" /> 
 
   <intent-filter> 
    <action android:name="android.app.action.DEVICE_ADMIN_ENABLED" /> 
   </intent-filter> 
  </receiver> 
 
 </application> 
 
</manifest> 

package com.itydl.lockscreen; 
 
import android.os.Bundle; 
import android.app.Activity; 
import android.app.admin.DevicePolicyManager; 
import android.content.ComponentName; 
import android.content.Intent; 
import android.view.Menu; 
import android.view.View; 
 
public class MainActivity extends Activity { 
 
 private DevicePolicyManager dmp; 
 
 @Override 
 protected void onCreate(Bundle savedInstanceState) { 
  super.onCreate(savedInstanceState); 
  setContentView(R.layout.activity_main); 
     //获取设备管理员对象 
    dmp = (DevicePolicyManager) getSystemService(DEVICE_POLICY_SERVICE); 
 } 
 
 /** 
  * 一键锁屏 
  * 
  * @param v 
  */ 
 public void lockScreen(View v) { 
  // 如果没有激活设备管理员，提醒用户做事 
  ComponentName who = new ComponentName(this, DeviceAdminSample.class); 
  if (dmp.isAdminActive(who)) {// true表示已经激活，测试管理员是否已经激活。这里的who其实就是我们自定义的空的广播接收者 
   dmp.lockNow();// 一键锁屏 
 
  } else { 
       ////帮助用户打开激活设备管理器的界面，让用户手动激活 
       /**根据官方文档，写出启动设备管理器的活动 
    * // Launch the activity to have the user enable our admin. Intent 
    * intent = new Intent(DevicePolicyManager.ACTION_ADD_DEVICE_ADMIN); 
    * intent.putExtra(DevicePolicyManager.EXTRA_DEVICE_ADMIN, 
    * mDeviceAdminSample); 
    * intent.putExtra(DevicePolicyManager.EXTRA_ADD_EXPLANATION, 
    * mActivity.getString(R.string.add_admin_extra_app_text)); 
    * startActivityForResult(intent, REQUEST_CODE_ENABLE_ADMIN); 
    */ 
    
    Intent intent = new Intent(DevicePolicyManager.ACTION_ADD_DEVICE_ADMIN); 
   intent.putExtra(DevicePolicyManager.EXTRA_DEVICE_ADMIN, 
      who); 
    intent.putExtra(DevicePolicyManager.EXTRA_ADD_EXPLANATION, 
      "设备管理器。。。"); 
    startActivityForResult(intent, 1); 
  } 
 } 
 
}